Boring chuck



Aug.. 13, 1935- J. A. |=ERGLJSO|\1y BORING CHUCK Filed Deo. 4, 1933 Maf A TTORNEYS.

Patented Aug. 13, 1935 UNITED STATES BORING CHUCK John A. Ferguson, West Millcreek Township, Erie County, Pa.

Application December 4, 1933, Serial No. '100,821

1 Claim.

The present invention is designed to provide a.

more accurate and convenient chuck for boring tools. With the present invention it is possible to accurately gauge the cut effected with each adjustment of the tool and the cut may be adjusted within very close limits. These adjustments may be accomplished while the head of the chuck is rotating so that it is not necessary to shut down the machine driving the chuck.

Features and details of the invention will appear from the specication and claim.

A preferred embodiment of the invention is illustrated in the accompanying drawing as follows:-

Fig.' 1 shows an elevation of the chuck partly in verticalsection in a plane through the axis.

Fig. 2 a detached view of the head.

Fig. 3 a rear view of the chuck.

Fig. 4 a front view of the chuck head.

socket 2 in which a shank 3 is secured. The shank 3 has the usual taper by means of which it may be readily secured in the machine. The head has a guide portion 4 of cylindrical shape and it has an enlarged tool guide projection 5 in which is arranged the under-cut, or dove-tailed guide slot 6. A tool-carrying block 1 is slidingly mounted in the slot 6. It is provided with a screw-threaded projection 8 and a tapered socket 9. A flanged nut IIJ is secured on the screwthreaded end 8 and engages a shoulder II on a bar I2. The end of the bar is tapered to iit the socket 9. The bar carries a cutting tool I3 which, as shown, is operating in the work I4.

The tool carrying block has a socket I5 in its 35 rear face and this is engaged by an arm I6 of a bell crank lever. The bell crank lever is pivotally mounted on a pin 16a, and the opposite arm I1 of the bell crank lever extends into an annular groove I8 in an axially adjustable sleeve I9. The 40 sleeve I9 is rotatively mounted on the guide portion 4 of the head. A spring 20 extends into a socket 2I in the block 1 and ngages a headed pin 22. The pin seats on a flanged ring 22a on -the projection 5. The sleeve I9 has a screw- 45 threaded projection 23 and a sleeve 24 has an internal screw thread operating on the screw threaded projection. The sleeve 24 has an annular shoulder 25 on its inner periphery and this engages a slot in a ring 26. A ring 21 is secured 50 on the ring 26 by screws 28 and operates against I marks the head. This has a screw-threaded f the outer face of the shoulder 25, thus locking the sleeve 24 with the ring .26. The ring 26 engages a shoulder 3a on the shank so that it is locked against axial movement on the head. Pins 29 lock the sleeve I9 and the ring 26 rotatively to- 5 gether. The sleeve I9 has an annular extension 30 which extends telescopically into a groove 3| in the sleeve 24. The outer faces of the sleeves I9 and 24 have knurled portions so that they may be readily grasped and thus they may be retarded. 10 y When the head is rotating and the sleeve I9 rotated relatively to the sleeve 24 and through the screw-threaded connection, the sleeve I9 may be adjusted axially along the head. This adjustment of the sleeve I9 carries with it the arm I1 15 of the bell crank lever and consequently the arm I6. Thus the tool carrier, or block 1 may be ad justed toward and from the center of the chuck to vary the cut. This adjustment may be a very fine one and the periphery of the sleeve 24 di- 20 rectly over the extension 30 is provided with a scale 32 which operates with relation to markings 32a on the extension. The plate 21 may be adjusted so as tol give a slight frictional resistance to a turning movement between the sleeve 24 and 25 I9 and in consequence the adjustment as made Will be maintained. A

In the operation of the device, the operator simply grasps the two sleeves I9 and 24 and this may be done while the chuck is rotating and by 30 holding one of the sleeves and turning the other a very accurate adjustment of the cutting bar may be effected.

What I claim as new is:-

In a boring chuck, the combination of a head; 35 a tool holder guide on the head; a holder on the guide; a bell crank lever pivoted on the head and engaging the holder; and two sleeves mounted on the head, one sleeve being movable relatively to the head and having an annular groove engaging one arm of the bell crank lever and an axially locked sleeve rotatively mounted on the head and having a screw-threaded connection with the axially movable sleeve, the axially movable sleeve r being adjustable axially through a relative rotative movement of said sleeves and said movable sleeve acting on the bell crank lever effecting the adjustment of the holder.

JOHN A. FERGUSON. 

